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提出了分页排序的概念和基于Quick Sorting的快速分页排序算法(Quick Page Sorting)以及基于Hinl缓存机制的算法实现技术。实验表明,在数万至数百万数据总量情况下,Quick Pagc Soring的速度比Quick Sorting快10倍左右,大大提高了应用系统的响应速度。 相似文献
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Rene Mueller Jens Teubner Gustavo Alonso 《The VLDB Journal The International Journal on Very Large Data Bases》2012,21(1):1-23
Computer architectures are quickly changing toward heterogeneous many-core systems. Such a trend opens up interesting opportunities
but also raises immense challenges since the efficient use of heterogeneous many-core systems is not a trivial problem. Software-configurable
microprocessors and FPGAs add further diversity but also increase complexity. In this paper, we explore the use of sorting
networks on field-programmable gate arrays (FPGAs). FPGAs are very versatile in terms of how they can be used and can also
be added as additional processing units in standard CPU sockets. Our results indicate that efficient usage of FPGAs involves
non-trivial aspects such as having the right computation model (a sorting network in this case); a careful implementation
that balances all the design constraints in an FPGA; and the proper integration strategy to link the FPGA to the rest of the
system. Once these issues are properly addressed, our experiments show that FPGAs exhibit performance figures competitive
with those of modern general-purpose CPUs while offering significant advantages in terms of power consumption and parallel
stream evaluation. 相似文献
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阐述了排序对数据处理的重要性。采用流行的跨平台的面向对象程序设计语言java实现了快速排序的算法,并从理论上进行了算法分析。 相似文献
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针对修正的PRI变换法无法分选重频参差雷达信号的缺点,提出了一种基于PRI谱的双门限雷达信号分选算法.该算法先对PRI谱设定双门限检测各个准PRI,再结合组合查看及序列搜索提取各个PRI.同时,构建了一种预分选、主分选结合的新型分选平台.预分选利用带有PowerPC的FPGA构架片上系统,完成对脉冲雷达信号的实时测量、AOA分类及数据存储;主分选采用DSP专职完成其他维参数的分选算法.谊分选新算法在保留抑制PRI子谐波优点的同时,对重频固定、抖动和参差的雷达脉冲信号都有较好的检测结果.视频信号源的大量测试表明,谊分选平台对普通雷达、PRI抖动和参差雷达、频率捷变雷达及一些特殊雷达均具有较好的分选能力. 相似文献
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We formulate and study a new computational model for dynamic data. In this model, the data changes gradually and the goal of an algorithm is to compute the solution to some problem on the data at each time step, under the constraint that it only has limited access to the data each time. As the data is constantly changing and the algorithm might be unaware of these changes, it cannot be expected to always output the exact right solution; we are interested in algorithms that guarantee to output an approximate solution. In particular, we focus on the fundamental problems of sorting and selection, where the true ordering of the elements changes slowly. We provide algorithms with performance close to the optimal in expectation and with high probability. 相似文献
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This paper shows that an N -node AKS network (as described by Paterson) can be embedded in a ( 3N / 2 ) -node twinbutterfly network (i.e., a multibutterfly constructed by superimposing two butterfly networks) with load 1, congestion
1, and dilation 2. The result has several implications, including the first deterministic algorithms for sorting and finding
the median of n log n items on an n -input multibutterfly in O ( log n ) time, a work-efficient deterministic algorithm for finding the median of n log
2
n log log n items on an n -input multibutterfly in O (log n log log n ) time, and a three-dimensional VLSI layout for the n -input AKS network with volume O(n
3/2
) . While these algorithms are not practical, they provide further evidence of the robustness of multibutterfly networks. We
also present a separate, and more practical, deterministic algorithm for routing h -relations on an n -input multibutterfly in O(h + log n) time. Previously, only algorithms for solving h one-to-one routing problems were known. Finally, we show that a twinbutterfly, whose individual splitters do not exhibit
expansion, can emulate a bounded-degree multibutterfly with (α,β) -expansion, for any α⋅β < 1/4 .
Received July 23, 1997; revised May 18, 1998. 相似文献
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对象全序化是基于优势关系的信息系统的一个重要内容,形式概念分析提供了对象排序的一个自然平台,然而传统的形式概念分析不能用来处理具有优势关系的属性。在优势概念格的基础上,对对象全序化方法进行了研究。基于优势关系形式背景,定义了对象在属性集上的优势度,进一步给出了对象的综合优势度,并利用综合优势度对对象进行全序化,并通过实例对方法进行了说明。研究进一步丰富了优势信息系统的相关理论。 相似文献
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Travis Gagie 《Information Processing Letters》2008,108(6):418-421
Sorting is a classic problem and one to which many others reduce easily. In the streaming model, however, we are allowed only one pass over the input and sublinear memory, so in general we cannot sort. In this paper we show that, to determine the sorted order of a multiset s of size n containing σ?2 distinct elements using one pass and o(nlogσ) bits of memory, it is generally necessary and sufficient that its entropy H=o(logσ). Specifically, if s={s1,…,sn} and si1,…,sin is the stable sort of s, then we can compute i1,…,in in one pass using O((H+1)n) time and O(Hn) bits of memory, with a simple combination of classic techniques. On the other hand, in the worst case it takes that much memory to compute any sorted ordering of s in one pass. 相似文献
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文档检索结果的排序和文本分类技术是解决垂直搜索、个性化信息检索、信息过滤等相关问题的核心技术。为了提高检索系统的性能,针对Lucene的基础排序算法,提出了一种融合位置相关和概率排序的改进方法。考虑到查询词在文档中出现的位置信息和概率排序对文档相关性的影响,利用位置相关的查询词权值和基于朴素贝叶斯分类算法的文档相关性概率值,对Lucene基础排序算法的评分公式进行改进。实验表明,该改进方法能够有效提高垂直搜索的准确率,使用户拥有更好的垂直搜索体验。 相似文献
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一种节省空间的排序算法 总被引:2,自引:0,他引:2
目前报道的一些排序算法,空间复杂度都比较大.提出了一种改进其空间复杂度的方法,其特点是算法简单、稳定,时间复杂度为O(n^2),空间复杂度为2n,达到下界.与传统的排序算法用变量与变量比较的思路不同,本文提出的是一种用变量与其分布区间进行比较的新思路.本算法特别适合那些范围确定且分布基本均匀的待排数据,也适合一般数据对象的排序. 相似文献
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ROY SPENCER 《计算机光盘软件与应用》2007,(7):42-49
是什么让杰出的3D艺术家在公司的主要团队成员中脱颖而出?为了回答这一问题,我们咨询了顶级游戏、VFX和建筑公司,让他们提名他们认为最有价值的玩家——接着要求被提名人提供在产业中脱颖而出的宝贵意见。[编者按] 相似文献
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星环形计算机局域网的性能研究 总被引:2,自引:0,他引:2
本文结合星形(Star)和环形(Ring)拓扑结构,提出了一种全新的LAN(Local Area Network)结构——星环形LAN.它以较低廉的代价在网络的几个主要性能指标上获得较大的提高.本文论述了星环形LAN(StarRing LAN)的设计思想和各性能指标的研究结果. 相似文献
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本文介绍了基于PROFIBUS现场总线和S7—300PLC的卷烟自动分拣系统。作者简述了工艺过程和需求,着重描述了系统的硬件构成与软件设计。 相似文献
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卷烟自动分拣系统在烟草工业中占举足轻重的作用.介绍了基于PROFIBUS现场总线和S7-300PLC的卷烟自动分拣系统,以及系统的组成与设计方法.该控制系统运行良好可靠,其综合效益十分明显. 相似文献